The authors study medium modifications of J/[psi] production in cold nuclear media in deuterium-nucleus collisions. They discuss several parameterizations of the modifications of the parton densities in the nucleus, known as shadowing, an initial-state effect. They also include absorption of the produced J/[psi] by nucleons, a final-state effect. Both spatially homogeneous and inhomogeneous shadowing and absorption are considered. They use the number of binary nucleon-nucleon collisions as a centrality measure. Results are presented for d+Au collisions at √S{sub NN} = 200 GeV and for d+Pb collisions at √S{sub NN} = 6.2 TeV. To contrast the centrality dependence in pA and dA collisions, they also present pPb results at √S{sub NN} = 8.8 TeV.

The d+Au data from RHIC, including the pA results from the fixed-target CERN SPS pA data, suggest increased importance of initial-state shadowing and decreasing nuclear absorption with increasing energy. This is not surprising since smaller x is probed at higher energy while absorption due to multiple scattering is predicted to decrease with energy. The CERN SPS data suggest a J/[psi] absorption cross section of about 4 mb without shadowing, and a larger absorption cross section if it is included since the SPS x range is in the antishadowing region. The d+Au RHIC data support smaller absorption, [sigma]{sup J/[psi]}{sub abs} ≈ 0-2 mb. Thus our predictions for J/{psi} and [Upsilon] production in pPb and Pb+Pb interactions at the LHC are shown for initial-state shadowing alone with no absorption or dense matter effects. We note that including absorption would only move the calculated ratios down in proportion to the absorption survival probability since, at LHC energies, any rapidity dependence of absorption is at very large.

The level of 'anomalous' charmonium suppression in high-energy heavy-ion collisions and its interpretation as a signal of quark-gluon plasma formation requires a robust understanding of charmonium production and absorption in proton-nucleus collisions. In a previous study we have shown that, contrary to common belief, the so-called J/[psi] 'absorption cross section', [sigma]{sub abs}{sup J/[psi]}, is not a 'universal constant' but, rather, an effective parameter that depends very significantly on the charmonium rapidity and on the collision energy. Here we present ugraded Glauber calculations with the EPS09 parameterization of nuclear modifications of the parton densities. We confirm that the effective 'absorption cross section' depends on the J/{psi} kinematics and the collision energy. We also make further steps towards understanding the physics of the mechanisms behind the observed 'cold nuclear matter' effects.

We present a wide study on the comparison of different shadowing models and their influence on J/[psi] production. We have taken into account the possibility of different partonic processes for the c{bar c}-pair production. We notice that the effect of shadowing corrections on J/[psi] production clearly depends on the partonic process considered. Our results are compared to the available data on dAu collisions at RHIC energies. We try different break up cross section for each of the studied shadowing models.

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We discuss aspects of open and hidden charm production in deuterium-nucleus collisions at RHIC and LHC energies. We describe calculations of the total c[bar c] cross section and the charm quark transverse momentum distributions. We next explain how shadowing and moderate nuclear absorption can explain the PHENIX J/[psi] dAu/pp ratios and predict the combined effect of shadowing and absorption in 6.2 TeV d+Pb collisions.